1. Field of the Invention
The present invention relates generally to a camera, and more particularly to a camera which records a picked-up image and positional data which is obtained by the global positioning system (GPS) during photographing.
2. Description of Related Art
The GPS is able to determine the three-dimensional position (latitude, longitude and altitude) of any point on the globe by receiving radio waves from a number of moving satellites.
Japanese Patent Provisional Publication Nos. 4-70724, 4-347977 and 7-288725 disclose systems in which a GPS unit connects to a camera (or is built in a camera), and the camera records a picked-up image and positional data obtained by the GPS unit on a recording medium. According to these systems, it is possible to know the photographing place of the recorded image with reference to the recorded positional data, which was obtained by the GPS unit, when the recorded image is regenerated, and it is also possible to retrieve a desired recorded image according to the photographing place.
Japanese Patent Provisional Publication No. 7-295025 discloses extending the life of a battery in the camera by controlling a power source circuit in accordance with surroundings of the camera recognized by the GPS unit. Japanese Patent Provisional Publication No. 9-233421 discloses a camera which is provided with a built-in printer.
The conventional camera provided with the GPS unit has the following problems. In an electronic camera, noise or harmful radiation is generated in an image pickup circuit, etc., particularly in a high-speed clock which drives a CCD sensor as an image pickup element. Then, if the GPS unit is connected to the electronic camera, the noise enters the GPS unit via a connection line, causes incorrect workings of the GPS unit and has a bad influence on the position measuring accuracy.
Moreover, the GPS unit cannot obtain positional data at a place where it is impossible to receive the radio waves from the satellites, that is, indoors, at the shade of a building, etc. If a user releases a shutter at such a place, it is impossible to obtain the correct positional data from the GPS unit, and thus, the incorrect data may be recorded.
Furthermore, there is no conventional camera which is provided with both of the GPS unit and a printer. If a camera is provided with the GPS unit and the printer, the positional data can be obtained by the GPS unit while the printer is printing the image. In this case, however, there is a problem in that the noise and harmful radiation increase while the printer is printing the image. The noise and harmful radiation disturb the reception of the positional data from the satellites, cause incorrect workings of the GPS unit and have a bad influence on the position measuring accuracy.